1. Field of the Invention
This invention relates to a drive axle and fluid pump assembly for a vehicle which requires a source of fluid under pressure. The drive axle and fluid pump assembly is particularly useful in providing a source of lubricating oil for cooling a friction brake of the type disclosed in U.S. Pat. No. 4,146,116.
2. Description of the Prior Art
There have heretofore been provided a number of axles which include mechanisms for pumping a liquid coolant to extract thermal energy generated by a plurality of discs in a friction brake such as those disclosed in U.S. Pat. Nos. 2,879,867; 2,940,549; 3,033,329 and 3,061,048. Those systems require additional, relatively complex elements to provide a pump mechanism at the wheel end and several require separate reservoirs and expansion chambers, as well as radiators for cooling the liquid. These designs are relatively complex and the additional elements provided at the wheel ends increase both the cost and weight of the vehicle.
Pumps have also been provided at locations other than at the wheel ends but those arrangements require a suitable location for mounting the pump and power transfer means for driving the pump in addition to a separate reservoir.